Investments as a Percent of Revenue

No definition available.

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- Definition

Number of Clients With Greater Than Ten Percent Revenue

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 275
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- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 41
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Business Information - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) Segment Entity	Dec. 31, 2017 USD ($) Entity	Dec. 31, 2016
Segment Reporting Information [Line Items]
Number of business segments (segment) \| Segment	1
United States
Segment Reporting Information [Line Items]
Long-lived assets \| $	$ 26.7	$ 36.6
Advisory Services
Segment Reporting Information [Line Items]
Number of clients that accounted for more than 10% of total revenues (entity) \| Entity	0	0
Revenue
Segment Reporting Information [Line Items]
Percentage of revenues from investments (less than)	1.00%
Revenue \| Geographic Concentration Risk \| United States
Segment Reporting Information [Line Items]
Percent of revenue per derived location	52.00%	70.00%	59.00%
Revenue \| Geographic Concentration Risk \| United Kingdom
Segment Reporting Information [Line Items]
Percent of revenue per derived location	29.00%	15.00%	27.00%